How Desktop Linux Should Behave

The promise of Desktop Linux (DL) has been long coming. It's made significant progress since the mid-90s when GNOME and KDE came out, giving Linux users a somewhat modern desktop to work upon. However, it's been 7 years and DL hasn't progressed much at all since then. Today, DL is still nothing more than a UNIX-clone with a task bar, a start menu, and a desktop with some icons on it. But why has DL evolved at such a glacial pace?